Newsletter Summaries Week 47 (2023)

SwiftData operations on background

Source: SwiftData Background Tasks

Use a custom ModelActor for the model to run operations on a background context.

modelExecutor = DefaultSerialModelExecutor(modelContext: context)

When passing objects between actors, we should use persistent identifiers, so there’s a convenience subscript on ModelActor

func visit(identifiers: [Country.ID]) {
  for identifier in identifiers {
    if let country = self[identifier, as: Country.self] {
      country.visited = true
    }
  }
}

Sized to fit bottom sheet in SwiftUI

Source: [Sized-to-fit SwiftUI bottom sheet

Matthew’s Dev Blog](https://matthewcodes.uk/articles/swiftui-size-to-fit-bottom-sheet/)

This is really nice and I’m definitely going to use it in one of my apps where I have a bunch of screen-context-related controls hidden behind a “settings” type button.

Handling TabView navigation with enums

Source: Handle TabView data in a type-safe way with Enums | Danijela’s blog

Somehow there were a lot of “Navigation-Architecture” related posts this week.

https://twitter.com/azamsharp/status/1725535808432611351

Enum based management of sheet navigation

Here’s another post by Antoine that goes in a similar direction. In a similar vein, there’s a sample for enum based sheet transition management @twannl

https://twitter.com/twannl/status/1597940020597374976

Number transition animation

Source: Animating number changes in SwiftUI | Sarunw Very pretty, but also very specific use-case of transition animation.
If everybody starts using this, all screens that use changing numbers will have the same feel to it. Not sure if that’s good or bad 😅

Text("\(number)")
    .contentTransition(.numericText())

Button {
    withAnimation {
        number = .random(in: 0..<200)
    }
} label: {
    Text("Random")
}

Nice “hack” to have a SwiftUI Text always take the maximum size given to it by it’s parent

Source: swift - How to scale text to fit parent view with SwiftUI? - Stack Overflow

ZStack {
    Circle().strokeBorder(Color.red, lineWidth: 30)

    Text("Text")
        .padding(40)
        .font(.system(size: 500))
        .minimumScaleFactor(0.01)
     }
}

In-depth article about GeometryReader

Source: [GeometryReader: Blessing or Curse?

by fatbobman

Better Programming](https://betterprogramming.pub/geometryreader-blessing-or-curse-1ebd2d5005ec)

New Trait system in SwiftUI

Source: Custom Traits and SwiftUI It’s nice and all, but I don’t quite see how they are different from EnvironmentKey, except for maybe being able to use this from both SwiftUI and UIKit.

Infinite width frame instead of Spacer in SwiftUI

Source: The alternative to SwiftUI’s Spacer

Either using a Spacer

struct ContentView: View {
    var body: some View {
        HStack {
            Image(systemName: "checkmark")
            Spacer()
            Text("Text")
        }
    }
}

Or a frame with its width set to infinity.

struct ContentView: View {
    var body: some View {
        HStack {
            Image(systemName: "checkmark")
            Text("Text")
                .frame(maxWidth: .infinity, alignment: .trailing)
        }
    }
}

Seems like a choice of personal preference.

StoreKit 2: ProductView and StoreView

Source: [Mastering StoreKit 2. ProductView and StoreView in SwiftUI.

Swift with Majid](https://swiftwithmajid.com/2023/08/08/mastering-storekit2-productview-in-swiftui/)

Another good overview article for the new features in StoreKit 2 for SwiftUI.